Analysis of hybrid exploitation of wind and wave power in the Mediterranean and the Black Sea

Abstract

The hybrid use of renewables enables resource complementation by other sources when one of them is inactive. This study focuses on wind and wave hybrids in the Mediterranean and the Black Sea with the aim of quantifying the potentials, directionality, correlation, and complementarity of the two sources. The investigation includes the spatial distributions and point-wise analysis capacity factors, the relationship between wave height and period, prevailing directions of wind and wave, bivariate probability analysis of wind and wave power, correlation of wind and wave power based on Pearson and Kendall's Tau methods, and complementarity analysis by computing the active hours of one source when the other is inactive. The energy density, correlation, and complementarity analysis are realized considering the working conditions of a wind turbine with eight different wave energy converters by taking into account their power matrices. ERA5 dataset is used as a source for the wind and wave data in the basin with over six-decade long time series for each grid point. The results indicate that the wind turbine possesses higher capacity factors. For the wind turbine, the spatial maximum is 0.5, whereas for the wave energy converters, this value is 0.16 for the Pelamis device with the highest performance among the considered devices. The relationship between the wave climate parameters is investigated by fitting the wave height and period time series to an exponential function in all study area. Results are provided as spatial distributions of function coefficient which is hoped to be useful for the researchers when only one of the variables is known. Bivariate probabilities are computed for wind and wave power, and it is seen that for the selected analysis points, the wave power has a potential between 1 and 1.5 kW/m in the most probable axial locations. Directional analysis of wind and waves resulted in a map of the prevailing directions in the study area showing that the Northwest is the dominant direction. Correlation analysis between the wind and wave power time series of devices indicates that a positive correlation is evident in the study area up to + 0.69. The main result from the complementarity investigation accompanied by the correlation analysis showed that wind complementing wave condition is much more dominant in the region.